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المبادئ الاساسية لهوائي النانو البصري (باوتاي) == The performance of Bow-tie optical nanoantenna

Author name: غفران عبد القادر حسن
Supervisor name: جواد عبد الكاظم حسن
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad

تصنيع جهاز استشعار حراري على اساس طلاء نانوي بواسطة جسيمات الجرافين النانوية المودعة على غلاف الالياف الضوئية منزوعة القلب == Fabrication of Thermal Sensor Based on Nanostructured Coating by Graphene Nanoparticles Deposited onto a Cladding Etched No-Core Fiber

Author name: حسين علاء فليح الربيعي
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad

ليزر الليف المشوب المتعدد الطول الموجي ذي مفتاح عامل النوعية المعتمد على الجسيمات النانوية كممتص مشبع == Multiwavelength Q-switched Doped Fiber Laser Based on Nanoparticle Saturable Absorbers

Author name: علي عبد الله سلمان
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad

تصميم وتنفيذ ضغط الاشارة المتراصف الليفي باستخدام الليف البلوري الفوتوني == Design and Implementation of In Line Fiber Pulse Compression using Photonic Crystal Fiber

Author name: علي احمد داود
Supervisor name: تحرير صفاء منصور
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad

التحقق من بروتوكول توزيع المفتاح الكمي بطريقة عدم الاعتماد على اجهزة القياس

Author name: احمد اسماعيل خليل
Supervisor name: شيلان خسرو توفيق
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

Generation of switchable and tunable wavelength erbium - doped fiber laser using ring cavity configuration

Author name: ورود
Supervisor name: Abdul Hadi M. Al-Janabi
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

متحسس رطوبة فعال يعتمد في بناءه على الالياف منزوعة القلب محفورة كيميائيا ومطلية بجسيمات اكسيد النحاس النانوية == Efficient Humidity Sensor Based on An etched No - core Fiber Coated With CuO Nanoparticles

Author name: هدى ثائر عبدالرزاق
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

التزامن لبروتوكولات توزيع المفتاح الكمي == Synchronization of Quantum Key Distribution Protocols

Author name: سلوى مراون صالح
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

ضغط الاشارة باستعمال مدخال الفابري بيروت نوع ايتالون المنغم ذو الليف البصري الفوتوني البلوري == Pulse Compression Using Tunable Etalons Fabry - Perot Photonic Crystal Fiber

Author name: سرى حسين محمود
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

المكررات الكمية المعتمد على مصدر فوتون منفرد متعدد الارسال == Quantum Repeaters Based on Multiplexed Single - Photon Source

Author name: وجدان محمود خضير
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

التحقق من التاثيرات الميكانيكية على اداء مرشح متداخل ماخ - زيندر

Author name: ايه ثابت يحيى
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

ليزر الليف البصري ذي النبضة القصيرة المعتمد على اكاسيد المعادن الانتقالية النانوية كممتص مشبع

Author name: سارة كاظم محسن الحيالي
Supervisor name: عبد الهادي مطشر عبد الجنابي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

متحسس معامل الانكسار مبني على تركيبة مدخال ماخ زيندر ذي الليف عديم القلب == Refractive Index Sensor Based On Coreless fiber - Mach Zehnder Interferometer Structure

Author name: سيف عقيل محمد
Supervisor name: عبد الهادي مطشر عبد
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

دراسة سطح المعدل بليزر فلوريد الاركون كمتحسس لتشتت رامان == Investigation of modified CR39 surface by ArF laser as an SERS sensor

Author name: رنا محمد طه البياتي
Supervisor name: حسين علي جواد
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:

توليد الارقام العشوائية الحقيقة بالاعتماد على زمن وصول الفوتون == True Random Number Generation Based on Photon Arrival Time

Author name: رغد سعيد حسن
Supervisor name: شيلان خسرو توفيق
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

تحسين اداء الترميز السعوي الطيفي بنظام الترميز البصري المتعدد باستخدام محزز الليف البصري نوع براغ == Performance Enhancement of SAE - OCDMA Using Fiber Bragg Grating

Author name: ابراهيم لؤي عبد الجبار
Supervisor name: تحرير صفاء منصور
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

مرشح ضوئي حزمي المرور متعدد التنغيم باستخدام الالياف البلورية الفوتونية == All - optical tunable bandpass filter using Photonic crystal fiber

Author name: ميثم صبري جابر
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

توليد الموجه المثالية باستخدام محزز براغ الليفي == Soliton Generation in Fiber BraggGrating

Author name: ليث طارق محمد
Supervisor name: تحرير صفاء منصور
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:

تنفيذ البوابة اكس اور بصريا بالكامل لمنظومات الاتصالات البصرية == Implementation of All Optical Exclusive - OR Gate for Optical Communication Systems

Author name: ياسمين سلمان كاظم
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: One of the most important techniques used to realize logic gates in optical networks is by all - optical signal processing.The most two important problems of electronic signal processing are high propagation loss of electronic signals and the high cost of the high speed electronics. Accordingly, these reasons led to converting to optical domain at higher frequencies (≥ 10 ????????/????) .The goal of this work is to implement all optical logic gates specifically exclusive - OR gate. Exclusive - OR gate have an important role in data encryption, parity checking, data encoding, bit pattern generation and matching, addressing, header recognition and many more applications. In this work an all - optical exclusive - OR logic function was achieved by a simulation software and implementing an experiment.In the simulation work, the exclusive - OR function was implemental by using a highly nonlinear fiber with a fiber nonlinear coefficient of 9.1 ????−1????????−1 , 0.135 km length non - degenerate with four wave mixing process and a NRZ - DPSK 10 GB/s signals.Experimentally the exclusive - OR function was implemented by using a highly non fiber with a fiber nonlinear coefficient of 10 ????−1????????−1and a 1 km length with bidirectional degenerate four wave mixing process. The optical signals that were used for the operation of the exclusive - OR function were NRZ - DPSK 40 GB/s signals. Results showed an exclusive - OR function associated with clear eye diagrams. In addition to that, exclusive - NOR function was also obtained experimentally in addition of these four maxterms (A + B, ????̅+ B, A + ???? ̅ and ????̅ +???? ̅ ).

قياس وتحليل الخسائر لموجات الموجع ذوات الفتحة المصنعة من سليكون على عازل == Measurements and Analysis of The Losses for Fabricated SOI Slot Waveguides

Author name: ميثم نعيم صالح
Supervisor name: مازن مانوئيل الياس
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: An interesting silicon photonics component is the slot waveguide. The discontinuity of the normal component of the displacement vector can be used to affect guiding of the majority of the electric field energy in a narrow low index gap when the field is polarized parallel to the silicon surface, that is, perpendicular to the silicon confining walls. By infiltrating nonlinear material into such a gap, one can simultaneously confine electric and optical fields achieving a high efficient optical modulation or switching that is becoming more desirable on optical communication. An array of 200 Silicon - on - Insulator (SOI) slot waveguide devices of varying slot widths, ribs widths, taper lengths and slot lengths are fabricated in each cell of a wafer fabricated at a commercial foundry. The cells are cleaved into individual chips after fabrication. Some chips are coated with thin films of polymers that fully infiltrated the slots. Measurements that consisted on spectral loss are made on the grating coupler waveguide devices of both coated and uncoated chips. Individual devices exhibited insertion losses varying from several dB up to values so great that the response is below the noise floor of the optical spectrum analyzer employed as a receiver. The chips that failed in the transmission test are primarily uncoated ones. Nominally identical devices on different chips exhibited nominally identical behavior. A commercial software program is used to simulate each of the structures that is included in the 200 devices test. The simulations are seen to show a degree of qualitative agreement with the experimental results. Comparison of the experimental measurements and the simulation results indicates that the loss inherent in a slot waveguide is quite low. Near loss free couplers from ridges to slots are achievable in case of coated devices, whereas the situation is different in case of uncoateddevices where a lot of energy is dissipated through the substrate. Use of a surface roughness model indicates that the excess loss that slots exhibit with respect to a ridge mode counterpart arise almost solely from surface scattering off the surface roughness. The increased loss in the case of the slot guide arises from the higher electromagnetic energy density at the surface of the guide due to the electric field discontinuity that is employed as a guidance mechanism in slot modes in contradistinction to ridge modes that are index - guided. Conclusions include some speculation as to the limits on the loss that can be achieved by variation the design of slot guides without any improvement in surface roughness over what is now available with fabrication in commercial foundries.

محزز الليف البصري نوع براغ لتحسس الحرارة والضغط == FIBER BRAGG GRATING FOR TEMPERATURE AND PRESSURE SENSING

Author name: فهد محمد عبد الحسين
Supervisor name: تحرير صفاء منصور
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Nowadays, the modern trends in optical sensing are to build simultaneous measurements sensors. In this work two schemes for simultaneous measurements sensors are presented. The first one is with dual FBGs peaks. Every FBG acts as sensing head. The first peak was used for temperature sensing and the obtained sensitivity is 10 pm/˚C and the second peak was used for temperature and pressure measurements with sensitivities 9.2 pm/˚C and 67 pm/ bar for temperature and pressure respectively.The other scheme consists of two sensing heads fabricated in the lab. The first sensing head is the Fabry - Perot interferometer which was used for load and strain measurements by controlling the size of its cavity reached to minimum value in micro scale (30). The sensitivity was increased to 4.07 nm/ N and 5.11 pm/ μɛ for load and strain respectively. This sensitivity for load is the highest that was recorded by micro cavity where previous works were reached to 1.37 nm/N. The second sensing head made by inscribing Bragg gratings inside the core of All Solid Photonic Band - Gap fiber toenhance its sensitivity that reached to 13.7 pm/˚C and 0.7 pm/μɛ for temperature and strain respectively which is more sensitive than previous works of our group in the institute that reached to 10 pm/˚C and 0.66 pm/μɛ for temperature and strain respectively. The obtained temperature sensitivity for the Bragg gratings is higher than previous work for Bragg gratings inscribed on All Solid Photonic Band - Gap Fiber where it was 12.04 pm/˚C.Strain sensitivities were almost the same.

التحقق عمليا من بروتوكول البينغ بونغ

Author name: علاء جبار جمعة
Supervisor name: شيلان خسرو توفيق
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Quantum cryptography uses basic laws of quantum physics to guarantee secure key exchange. The key can be used with unprecedented confidence in any classic cryptographic protocol, where it increases the security to the maximum achievable value. The goal of this work is to encrypt the message directly without need to generate the secure key by using the modified Ping - Pong Protocol. A quantum cryptography system based on Modified Ping - Pong Protocol was designed and implemented for the first time. A polarization - entangled photons were generated by a source using PPKTP crystal inside a polarization Sagnac interferometer at telecom wavelength 1550 nm and a fiber length of 15 Km. In this experiment, Bob prepares entangled photons, sends one photon to Alice by optical fiber to perform one out of four operators according to the message. The modulated photon is sent back to Bob. Then the Bell’s state measurement is applied to extract the message according to the Alice’s coding. The HOM - dip of the two - photon interference was verified to guarantee perfect system performance. The final results showed the switching between the Bell’s states, |????+⟩ and |????−⟩ as the phase of the phase modulator was changed by Alice achieving an acceptable coincidence count of about 625 counts per 30s. These results proves also two photon interference needed to test Bell’s enquality.

الليف البلوري الفوتوني لاستشعار المجال المغناطيسي == Photonic crystal fiber magnetic sensor

Author name: احمد عدنان محمد
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Master
Language: English
University location: Baghdad
First pages:
Abstract: Photonic crystal fiber (PCF) is widely used for sensing applications. In this work, magnetic sensor based on solid core - PCFs for sensing magnetic field was presented. The general structure of the sensor applied is by splicing short lengths of PCF (LMA - 10) with conventional single mode fiber (SMF - 28) in one side and using free space connector from other side. A laser diode with different wavelengths (850, 1060 and 1300 nm) has been used as a light source, where a high sensitive optical spectrum analyzer (OSA) was used to monitor and record the transmitted/reflected spectra.The present work demonstrates the results of the infiltration of the air holes for the PCFs by fluids instead of air. For magnetic sensing, the magnetic fluids being used were prepared and standard ????????3????4 to infiltrate the air holes for the solid core PCF (LMA - 10) which leads to change in the effective refractive index of the PCF, which in turn affects the transmission of the laser inside the PCF due to the value of the refractive indices of the magnetic fluids. The experiments show that the power of transmissionspectrum of the laser had decreased after infiltration without any change in central wavelength of the laser diode the reason is that after PCF air holes infiltration, the effective refractive index has been changed but still within total internal reflectionwhich leads to loss of some fundamental modes, in turn leads to decrease the power of transmission spectrum. The decrease of the transmitted power in the case of standard has been higher than it in the case of prepared ????????3????4 because of the differencein concentration between standard and prepared magnetic fluids. The power of transmission spectrum after PCF infiltration will be increased with increasing magnetic field. Higher sensitivity has been obtained that reached 5.809 nW/mT which consideredhigher than previously published works on PCF magnetic sensors.

التحقق من تاثير عدم استقرارية بلاتو - رايلي في عملية سحب ليف شبه المواد انديوم - بوليمر == Investigation of the influence of the Plateau - Rayleigh instability in fibre drawn indium - PMMA metamaterial

Author name: احمد عبد الكريم علي
Supervisor name: عبد الهادي مطشر الجنابي
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
Abstract: Metamaterial is a synthetic composite material with a structure such that it exhibits properties not usually found in natural materials. Fibre drawing method has been used in producing Poly - methyl methacrylate (PMMA) - indium wires metamaterials. PMMA and indium are having relatively the same glass transition temperature making them suitable for co - drawing. The fiber filaments must be drawn to smaller diameters to shift the metamaterials response to higher frequency. At these dimensions the metal filaments inside the fiber become unstable and break - up at random intervals. This instability is due to a phenomenon known as the Plateau - Rayleigh InstabilityWell known Tomotika model for the growth in the varicosity in the surface of fluid extended inside another fluid was modified to describe the fluctuations (instability) of inner core diameter for metamaterials drawing inside radiative furnace. Modified Tomotika model was used to investigate the instability growth of the indium wire diameter produced by co - drawing of indium metal embedded in a PMMA polymer.The critical parameter for the wire breaks is the wavelength of perturbations. A MATLAB model was used to describe a small drawing ratio (neglecting the wavelength of fluctuations effect). The experimental and modeling results are almost match when a very small temperature variation occurred. So the observed fluctuations in diameter can be reconciled with the Plateau - Rayleigh instability.For larger fluctuations (large drawing ratio) the wavelength of fluctuations was analyzed and sequential breakup on different length scales was observed. We infer limits to wire dimensions that can beachieved using the chosen material system and identify a path for extending drawing methods to fabricate smaller wires.Finally, simulation for deep subwavelength wave propagation inside wire metamaterials depending on the unit cell manipulation was performed. CST microwave studio software had been used to simulate wave propagation inside linear and 90o corner waveguide as well as equal arms beam splitter (50/50). It’s applicable to waveguiding 40cm wavelength in about 2.4 cm waveguide.

كتابة محزز الحيود نوع براك على ليف بصري بشكل حرف D باستخدام ليزر الاكسايمر نوع كربتون فلورايد == Writing Of A Bragg Grating On A D-Shaped Optical Fiber Using The KrF Excimer Laser

Author name: شيماء رياض محمد علي ال طحان
Supervisor name: خليل ابراهيم حاجم
General topic: Laser Science
Degree: Doctorate
Language: English
University location: Baghdad
First pages:
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